99% of those who trade whether as hobby or serious money seldom think it as a business cause they don't have to live off of it or when you in your twenties don't even think that your retirement money is real, I never did. I didn't take it serious in the beginning, it was just something that was fun. It wasn't till I lost a huge sum in the 80s turned my mental aspects that it was a business and had to manage it like any other business.
Yes, I have seen many who along the way make a huge chunk out, the market gods allowing that to happen and watched all of them end up bankrupt or worse of taking their life as all of a sudden they looked at what they did in markets was more important than their family. There are reasons there are percentages used by many for risk. It is not just risk per trade, but risk of ruin of why there are percentages. And just cause one has losing trades, doesn't not mean they are personality wrong, they just wrong at the time and if they stay with a business concept and percentages, they have better chances of doing right. Long term risk low enough times with well backtested method, laws of averages one will nail larger winning trades, but if you designed and tested correctly, have to expect the unexpected as part of the business oddities that unexpected large profits and losses will happen in one's trading life.
The posts I enjoy now are from 10 plus years ago, very seldom do I read anything of worth as those who know seldom write and much of ET is blowing off steam and they gripe about whatever.